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6th,

Saturday, .......... TIth, ...................................

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2 m. 7 s.:1 m. 164 s., and therefore by adding this : to 6 m. gives 7 m. 164 s. for the equation at the time. required.

TABLE
Of the Equation of Time for every fifth Day.
Wednesday, Jan. Ist, to the time on the dial add 3
Monday, ..........
Thursday, ......... 1
Tuesday, .........

21st, .............."
Sunday, ..."

26th, ............ Friday ........... 31st, .......

LUNAR PHENOMENA.

Phases of the Moon.
Last Quarter, 4th day, at 10 m. past 4 morning
New Moon, 12th .......... 54 ............. 8 ............
First Quarter, 20th .......... O ....
Full Moon, 26th .......... 11 .......... 5 afternoon.

Moon's Passage over the Meridian. The following table shows at what time the Moon will pass the meridian of the Royal Observatory on certain days during this month, when observations may be conveniently made, if the weather prove favourable. For any other meridian a slight reduction is necessary, which depends upon the longitude of the place as well as the Moon's horary motion.

TABLE
Of the Moon's Passage over the first Meridian,
January 3d, at 3 m. after 5 in the morning
4th, ... 47

...........

6 ......................

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4 in the afternoon

18th, 19th,

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20th
21st,

7 in the evening
220, ...
23d, ... 10
24th, ... 15

25th, ... 17 .........
On the 26th of this month the Moon will be totally

22 26

eclipsed, which will be partly visible at Greenwich; the circumstances being as follow, viz.

h. m. S.
Beginning of the eclipse .................
Moon rises eclipsed .........................

18 46
Beginning of total darkness ............
Ecliptic opposition ..........................

10 45
Middle ..............................................

5 11 28
End of total darkness ...........................

6 0 30
Duration of total darkness ................... 38 4
Whole duration of the eclipse ............... 3 33 6
Digits eclipsed 200 47' 32".
PHENOMENA PLANETARUM.

Phases of Venus. We have already shown that the phases of this beautiful planet are subject to variation, like those of the Moon, and have explained the method by which they are calculated, as well as solved the problem relative to her maximum brilliancy (see T.T for 1819); we shall therefore only give the results of these calculations for the first of each month in the present year.

January 1st, {Illuminated part = 11.99878 digits

y "(Dark part ........ = 0·00122 Venus is, therefore, very near the point of her greatest illumination; but our young readers should be reminded that this is by no means that of her greatest brilliancy. On this subject see T. T. for 1819, p. 51.

Eclipses of Jupiter's Satellites. From the number of Jupiter's moons or satellites, and the rapidity with which their revolutions are performed, they are frequently eclipsed by passing through his shadow. These bodies, however, are too small for their eclipses to be subject to common observation, and indeed require a good telescope to observe them with accuracy. The young observer should also be at his telescope a little before the eclipse is expected to take place, that he may be able to observe it with all possible steadiness. To

17th ......

assist him in these respects, we shall insert the times of such of the eclipses of the first and second satellites as are visible at Greenwich.

Emersions.
First Satellite, ... 1st day, at 25 m. 22 s. after 11 at night

3d .......... 54 ... 14 ......... 5 evening
9th .........

1 morning
10th .........

7 evening

9 ............ 24th ....

ll night 26th.

6 evening Second Satellite, 6th ..........

0 morning 23d ......... 47 ... 18 .........

6 evening 30th ......... 23 ... 57 .......... 9 .............

Form of Saturn's Ring. For such explanations as are necessary to enable our readers to apprehend the principal circumstances of this singular phenomenon, we must refer to T.T. for 1819. "We shall therefore only insert the results for every third month, leaving the calculations as exercises for our astronomical students. January 1st,

o s Transverse axis .......... 1.000

As I Conjugate axis ............ – 0.343 Transits and Altitudes of the Planets. For the information of such of our readers as wish to observe the planets in their passage over the meridian, we shall insert the times of their transit for every 6th day, and their altitudes when on the first meridian. The time of passing any other meridian may also be readily found by adding or subtracting that answering to the difference of longitude; and the meridional altitudes will differ very little for any other part of Great Britain. From having the meridional altitude and the latitude of the place of observation, the declination may be obtained by simple subtraction, for it is always equal to the difference between the altitude and the co-latitude of the place. When the altitude is the greater quantity, the declination, in our latitude, is north ; but when it is the less, it is south. .

Example.—The meridional altitude of Mercury, at

everidian. The dily found bence of

may answering altitude atain. Loft

h.

m

.

39

the Royal Observatory, on the 1st of May, 1823, is 54° 19'; and as the co-latitude is 38° 29', we have 54° 19' — 38° 29' = 15° 50' N. for the declination of the planet on that day.-Again, on the 1st of September, 1823, the altitude of Venus, when on the first meridian, is 26° 46'; and consequently her declination at that time will be 38° 29' - 26° 46' = 11° 43' S.

TABLE Of the Transits and Meridional Altitudes of the

Planets. 1st 7th 13th 19th 25th

TRANSITS.

h. m. Mercury 11 56 mor. 0 15 aft. Venus 09aft. 0 16

0 22 0 28 0 33 Mars 1 19 aft. 1 13

1 0 0 53 Jupiter 8 5 even. 8 26

7 33 7 8 Saturn 7 21 even. 6 55

6 29 G. Sidus 11 48 mor. 11 24

11 0 10 36

MERIDIONAL ALTITUDES, Mercury 13037'

14023'

160 6 180454 22°15' Venus 14 53

15 36

16 34 18 16 20 8 Mars 17 8

18 0

19 11 20 29 21 54 Jupiter 57 12 57 8

57 7 57 9 Saturn 48 48

48 46

48 49 48 53 48 59 G. Sidus 14 56

14 57

14 58 15 0 15 3

Other Phenomena. Mercury will be in his superior conjunction about 1 in the morning of the 3d; and Saturn will be stationary on the 4th of this month. The Moon will be in conjunction with the bright star o in Scorpio, at 38 m. past 3 in the afternoon of the 8th; and, at the same time, Mercury will be in conjunction with Venus. They will consequently be seen above each other, Mercury being only 65south of Venus. The Moon will be in conjunction with Venus at 21 m. after 7 in the evening of the 12th ; with Mercury at 34 m. past 10 the same night; and with Mars at 43 m. after 6 the next evening. Jupiter will be stationary on the 21st. Mercury will be in conjunction with Mars on the 22d, the former planet being at that time 27 south of the latter. Saturn will also be in quadrature at 45 m. past 7 in the morning of the 24th.

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Thus the celestial phenomena of this month supply bay the young astronomer with numerous opportunities one of exercising his powers of observation; and, by

combining practice with theory, of advancing in his në progress up the mount of that sublime science. But of the while he thus climbs the steep ascent, and surveys 4. that cerulean vault, so gloriously illuminated with

celestial radiance, the sensible mind will feel more

than ever grateful for that faculty which enables him eft to enjoy this astonishing spectacle, and

Take in, at once, the landscape of the world
At a small inlet, which a grain unight close,

And half creates the wonderous world we see. YOUNG. Ought he not, too, on contemplating such a scene, to experience something of the feeling expressed by the same poet, when he exclaims,

Who turns his eye on Nature's midnight face
But must inquire What hand behind the scene,
• What arm Almighty, put these wheeling globes

In motion, and wound up this vast machine?
• Who rounded in his palm those spacious orbs ?

Who bowled them flaming thro' the dark profound,
. And set the bosom of old Night on fire?
Nature's Controller, Author, Guide, and End!

The Naturalist's Diary

For JANUARY 1823.
Thou hast thy beauties : sterner ones, I own,

Than those of thy precursors; yet to thee

Belong the charms of solemn majesty
And naked grandeur. Awful is the tone
Of thy tempestuous nights, when clouds are blown

By hurrying winds across the troubled sky;

Pensive, when softer breezes faintly sigh
Through leafless boughs, with ivy overgrown.
Thou hast thy decorations too; although

Thou art austere ; thy studded mantle, gay
With icy brilliants, which as proudly glow

As erst Golconda's; and thy pure array
Of regal ermine, when the drifted snow

Envelopes Nature; till her features seem
Like pale, but lovely ones, seen when we dream.

B. BARTON.

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